//app.js是程序的主入口 一切请求从此开始
var createError = require('http-errors');
var express = require('express');
var path = require('path');
var cookieParser = require('cookie-parser');
var logger = require('morgan');

//导入项目所需要的路由
var indexRouter = require('./routes/index');
var userRouter = require('./routes/user');
var videoRouter=require('./routes/video');

//创建服务器实例对象
var app = express();

// view engine setup 常用配置设值
app.set('views', path.join(__dirname, 'views'));
app.set('view engine', 'jade');

app.use(logger('dev'));
app.use(express.json());
app.use(express.urlencoded({ extended: false }));
app.use(cookieParser());
app.use(express.static(path.join(__dirname, 'public')));
app.use('/video',express.static(path.join(__dirname, 'files')));

//解决跨域问题
// ajax->只能访问相同域名相同端口下的资源
app.all("*", function (req, res, next) {
  res.header('Access-Control-Allow-Origin', '*')
  res.header('Access-Control-Allow-Headers', 'X-Requested-With, mytoken')
  res.header('Access-Control-Allow-Headers', 'X-Requested-With, Authorization')
  // res.setHeader('Content-Type', 'application/json;charset=utf-8')
  res.header('Access-Control-Allow-Headers', 'Content-Type,Content-Length, Authorization, Accept,X-Requested-With')
  res.header('Access-Control-Allow-Methods', 'PUT,POST,GET,DELETE,OPTIONS')
  res.header('X-Powered-By', ' 3.2.1')
  console.log(req.method);
  if (req.method.toLowerCase() == 'options')
    res.send(200);  //让options尝试请求快速返回
  else
    next();
});



// 路由设置
app.use('/', indexRouter);
app.use('/user', userRouter);
app.use('/video',videoRouter);

// catch 404 and forward to error handler
app.use(function (req, res, next) {
  next(createError(404));
});

// error handler
app.use(function (err, req, res, next) {
  // set locals, only providing error in development
  res.locals.message = err.message;
  res.locals.error = req.app.get('env') === 'development' ? err : {};

  // render the error page
  res.status(err.status || 500);
  res.render('error');
});


module.exports = app;
